The present invention relates to a multi-directional switch comprising a plurality of manual switches and used in electronic devices such as a portable telephone, video camera, car radio and others.
The multi-directional switch comprises a plurality of fixed contacts circularly arranged in a housing, and an operating plunger tiltably provided in the housing and having a plurality of branches, each having a movable contact which can be contacted with a corresponding fixed contact in the housing by manipulating the operating plunger, thereby producing a specific signal.
FIG. 10 is a plan view of a multi-directional switch disclosed in the Japanese Utility Model Application Laid Open 1-111431, FIG. 11 is a sectional side view of the switch.
A multi-directional switch has four push button switches 12 on a substrate 11, disposed on a cross line. An operating plunger 13 has an operating lever 13a, a spherical portion 13c, a conical recess 13d, four restricting portions 13b on the cross line, each restricting portion 13b has a parallelepiped shape. The operating plunger 13 is rotatably held by a spherical portion 15a of a cover of a case 14 and a conical support 16 secured to the substrate 11.
The plunger 13 has four receiving arms 13e and four operating arms 13f in the cross line direction. A spring 17 secured to the case 14 engages with each receiving arm 13a, thereby holding the operating lever 13a of the plunger 13 in the vertical position.
In accordance with the above described construction, the inclination direction of the plunger 13 is restricted by restricting portions 13b to four directions on the cross line. Four perforations 18 are formed in the spherical portion 15a, each corresponding to the restricting portion 13b. Thus, the plunger 13 can be tilted, inserting the restricting portion 13b in the perforation 18. If the plunger 13 is pushed in other directions than the cross line direction, the plunger 13 can not be tilted since the restricting portion 13b engages with a stopping portion 15b of the cover 15.
When the plunger 13 is tilted in one of the four directions the operating arm 13f pushes a push button 12a of one of the switches 12.
In the conventional switch 10, since the conical support 16 is provided in the central position of the switch, it is impossible to modify the switch to a versatile switch in which an additional push button switch is provided at the central position. Further, in such a versatile switch, the plunger must be provided so as to be vertically moved to operate the central switch. However, in the conventional switch, the height of the switch becomes large.
In addition, since the spherical portion 13c is provided in the central portion, a vertical guide portion for vertically guiding the operating lever 13a is provided on the spherical portion 15a, the height of the switch becomes large, and the construction thereof becomes complicated.
An object of the present invention is to provide a multi-directional switch having a central switch.
Another object is to provide a multi-directional switch which may be reduced in size and height and simple in construction.
According to the present invention, there is provided a multi-directional manual switch comprising, a substrate having a central fixed contact and a plurality of peripheral fixed contacts and a central movable contact and a plurality of peripheral movable contacts, each of the movable contacts being provided above each of the fixed contacts so that opposite contacts form a unit switch, a holding plate having a first holding corner formed on an underside thereof and mounted on the substrate, an operating plunger having a plurality of radially extending arms, and slidably, mounted in hole formed in the holding plate, and rotatably held in the first holding corner so as to be tilted about the first holding corner, and a plurality of projections formed on the underside of the plunger comprising a central projection and a plurality of peripheral first projections, each of the projections being provided corresponding to the movable contact.
The operating plunger is axially slidably held in the holding corner.
A plurality of second holding corner are formed on the underside of the holding plate, a peripheral plunger is provided between the peripheral projection and second holding corner so as to be pivoted about the corner, a second projection is formed on the underside of the peripheral plunger, each of the peripheral fixed contacts is offset from the peripheral projection and disposed so that the peripheral movable contact is depressed by the second projection.
The stroke between a top of the central projection and a surface of the central fixed contact is smaller than a stroke between a top of the second projection and a surface of the peripheral fixed contact.
The length between the peripheral first projection and the second projection is longer than a length between the second projection and the second holding corner.
These and other objects and features of the present invention will become more apparent from the following detailed description with reference to the accompanying drawings.